Pyogenic infection of the sacro-iliac joint. Report of thirteen cases.

Thirteen cases of infectious sacro-iliitis caused by pyogenic organisms are reported and compared with thirty-four cases in the literature. Staphylococcus was the commonest infecting organism (six cases). Two clinical patterns were noted, acute (nine cases) and subacute (four cases). Treatment was by antibiotics and bed rest in all patients. Surgery was indicated for diagnosis in three patients and for abscess in three patients. All of our patients had very good functional recovery.